Game loops are an interesting psychological topic. The rhythm at which a player experiences a game, experiences trials, has breaks, and is issued decisions. Today, I'd like to talk about some concepts of gameplay loops, that of feel and flow.
I'll define feel as the emotional reaction to participating in a certain part of a gameplay loop. For an action game, feel would be the reaction a player has from successfully connecting an attack with an opponent, executing a combo, or simply hitting a desctructible portion of the environment. The environment around the player reacts to the player's actions in some way, feedback is provided (visually and auditory) and the player has a reaction to it. This is the feel we all talk about when we are discussing how it feels to play a game: what is the player's base reaction to making a decision and executing an input successfully or unsuccessfully.
Flow I'll define as the rhythm of choices. Most game can be boiled down to a series of interesting decisions, says Sid Meier. Flow is the rate at which those decisions are presented.
I'll give an example. Let's say you are playing a level of Mario, one with a series of platforms, each incrementally higher than the last, followed by two parallel walls at which the player must execute multiple wall jumps to reach the goal at the top. Now, this may not seem like a series of decisions, but in reality, it is. Each jump is a timing choice, executed by the player, and interpreted by the game. A poorly timed jump results in failure whereas a well-time jump results in success. The flow here, then, is the rate at which these decisions are presented. In this level for example, let's say if the player ran at top speed towards the platforms, they'd have to jump every half second to scale the platforming challenge. The player is presented with a rhythm at which their choices are made. The choice here, however, is very simple: jump or don't jump. However, this serves as a good example of flow. Note that we cannot comment on whether or not this is good or bad flow, because that is a question that is hard to answer without feedback from the player. Some games may require faster flow (more frequent decisions), while others would be better served with a slower pace. It all depends on the feel of the player tapping into the flow.
Let's take another, more complex, example. Character action games are probably the most obvious examples of a game with strong feel and flow. Each action the player character makes has a very noticeable impact on the environment and the world around them, gained from the visual and auditory feedback given back to the player on execution. Hit an enemy with an attack and they reel backwards while the player character digs in, producing a sound effect. Another enemy looms, and the player is now forced to make a decision on what to do next. Here, in the character action genre, the player has a multitude of decisions. The player can attack that enemy with any number of possible abilities, dodge away, keep fighting the enemy they are already engaged to, or simple run away, among a number of other possibilities.
One of the keys that separates a good action game with a poor one is that sense of rhythm or flow. Flow is the rate at which meaningful choices are presented to the player. Too many at once, and the player is overwhelmed. Too few, and the player becomes bored and disengaged. In a character action game, enemies attack the player at a predictable, rhythmic pace. This allows the player to form a rhythm of combat in their head, providing them the opportunity to understand when their next decision point will be, and reacting appropriately. Have you ever been frustrated by a game that very quickly and cheaply made quick work of your player character? It's likely because whatever happened was unexpected. Most of the time, unexpected outcomes come from actions the game takes towards the player that do not fall in line with a pre-established flow. A cheap shot, if you will. A combat action taken by the enemy that is out of the rhythm pre-established by the game. Tetris would never drop a block that falls immediately out of the blue. The player knows the decision points in Tetris, it's a predictable game. This allows the player to play to the flow, become locked in their engagement, and be awarded appropriately.
In these games we have decision points, defined by the flow, and we have those decisions, whose feedback and effect inform the feel. Both of these are inextricably linked, as they both affect a player's moment-to-moment perception of a game, and, I'd argue, a game's "fun factor".
Upending expectations can be fun, but meeting expectations is a very important to defining a clear and fun moment-to-moment experience. Once a game establishes a flow, however, it might be fun and interesting to mess with it.